import random
import unittest

class TestSequenceFunction(unittest.TestCase):
    def setUp(self):
        self.seq = range(10)

    def testshuffle(self):
        random.shuffle(self.seq)
        self.seq.sort()
        self.assertEqual(self.seq,range(10))

    def testchoice(self):
        element=random.choice(self.seq)
        self.assert_(element in self.seq)

    def testsample(self):
        self.assertRaises(ValueError,random.sample,self.seq,20)
        for element in random.sample(self.seq,5):
            self.assert_(element in self.seq)

if __name__ =='__main__':
    unittest.main()